sighing

Sighing is a deep, prolonged breath that follows a normal breath. It is often characterized by a longer inhalation, sometimes accompanied by an audible exhale, and may occur spontaneously or be produced voluntarily. In humans, a sigh increases lung volume beyond the usual tidal breath and can reset the breathing pattern.

Physiologically, a sigh helps re-expand small airways and alveoli, improving lung compliance and gas exchange. It can act as a corrective mechanism when breathing becomes shallow or irregular. Sighs occur at irregular intervals and can be influenced by emotional or physical states, making them both a reflexive and a conscious component of respiration.

Causes and contexts vary. In healthy individuals, sighing frequently occurs in response to fatigue, stress, sadness, relief, or surprise, and may also be used deliberately in practices such as meditation or in social settings to communicate emotion. Frequent sighing can be associated with anxiety disorders, depression, or dyspnea-related conditions, where it may reflect changes in breathing patterns or compensatory respiratory effort.

Social and research perspectives note that sighing can convey internal states to others and may serve communicative or regulatory functions. In scientific study, sighing is examined as part of respiratory patterns in sleep, mood disorders, and autonomic regulation, helping to understand how emotional states interact with breathing dynamics.